Asteroid family

Asteroid families become visible as distinct concentrations when asteroids are plotted in the proper orbital element space (i_p vs a_p). Some prominent families are the Vesta, Eunomia, Koronis, Eos, and Themis family located in different (colorized) regions of the asteroid belt.

An asteroid family is a population of asteroids that share similar proper orbital elements, such as semimajor axis, eccentricity, and orbital inclination. The members of the families are thought to be fragments of past asteroid collisions. An asteroid family is a more specific term than asteroid group whose members, while sharing some broad orbital characteristics, may be otherwise unrelated to each other.